A difficult obstacle associated with the exploration and production of oil and gas is management of significant ocean currents. These currents can produce vortex-induced vibration (VIV) and/or large deflections of tubulars associated with drilling and production. VIV can cause substantial fatigue damage to the tubular or cause suspension of drilling due to increased deflections. VIV suppression devices of a variety of sizes and shapes can be attached to the tubular to suppress these ocean current effects on the tubular. One such device is a helical strake, which consists of vanes that are wrapped in a helical pattern around the tubular. While helical strakes, if properly designed, can reduce the VIV fatigue damage rate of a tubular in an ocean current, they typically produce an increase in the drag on the tubular and hence an increase in deflection. Thus, helical strakes can be effective for solving the vibration problem at the expense of worsening the drag and deflection problem.
Another solution is to use fairings as the VIV suppression device. Typical fairings have a substantially triangular shape and work by streamlining the current flow past the tubular. A properly designed fairing can reduce both the VIV and the drag. Fairings are usually made to be free to weathervane around the tubular with changes in the ocean current. Fairings are usually designed with a specific chord-to-thickness ratio (chord divided by thickness), with the chord measured from the tip of the fairing nose to the tip of the fairing tail, and the thickness measured across the fairing normal to the flow direction, thus the chord is typically at least a little larger than the thickness.
One of the most important components of the overall system cost of fairings is the installation costs. For many applications, the cost of installation can exceed the cost of the fairing system hardware. In particular, drilling risers require fast installation times for fairings due to the very large cost associated with the drilling rig, where the rig is priced by the day. Fairing installation, however, can be time consuming, which in turn drives up costs.